coreutils: Options for date
21.1.6 Options for ‘date’
-------------------------
The program accepts the following options. Also see ⇒Common
options.
‘-d DATESTR’
‘--date=DATESTR’
Display the date and time specified in DATESTR instead of the
current date and time. DATESTR can be in almost any common format.
It can contain month names, time zones, ‘am’ and ‘pm’, ‘yesterday’,
etc. For example, ‘--date="2004-02-27 14:19:13.489392193 +0530"’
specifies the instant of time that is 489,392,193 nanoseconds after
February 27, 2004 at 2:19:13 PM in a time zone that is 5 hours and
30 minutes east of UTC.
Note: input currently must be in locale independent format. E.g.,
the LC_TIME=C below is needed to print back the correct date in
many locales:
date -d "$(LC_TIME=C date)"
⇒Date input formats.
‘--debug’
Annotate the parsed date, display the effective time zone, and warn
about potential misuse.
‘-f DATEFILE’
‘--file=DATEFILE’
Parse each line in DATEFILE as with ‘-d’ and display the resulting
date and time. If DATEFILE is ‘-’, use standard input. This is
useful when you have many dates to process, because the system
overhead of starting up the ‘date’ executable many times can be
considerable.
‘-I[TIMESPEC]’
‘--iso-8601[=TIMESPEC]’
Display the date using an ISO 8601 format, ‘%Y-%m-%d’.
The argument TIMESPEC specifies the number of additional terms of
the time to include. It can be one of the following:
‘auto’
Print just the date. This is the default if TIMESPEC is
omitted.
‘hours’
Append the hour of the day to the date.
‘minutes’
Append the hours and minutes.
‘seconds’
Append the hours, minutes and seconds.
‘ns’
Append the hours, minutes, seconds and nanoseconds.
If showing any time terms, then include the time zone using the
format ‘%:z’. This format is always suitable as input for the
‘--date’ (‘-d’) and ‘--file’ (‘-f’) options, regardless of the
current locale.
‘-r FILE’
‘--reference=FILE’
Display the date and time of the last modification of FILE, instead
of the current date and time.
‘-R’
‘--rfc-email’
Display the date and time using the format ‘%a, %d %b %Y %H:%M:%S
%z’, evaluated in the C locale so abbreviations are always in
English. For example:
Fri, 09 Sep 2005 13:51:39 -0700
This format conforms to Internet RFCs 5322
(https://tools.ietf.org/search/rfc5322), 2822
(https://tools.ietf.org/search/rfc2822) and 822
(https://tools.ietf.org/search/rfc822), the current and previous
standards for Internet email. For compatibility with older
versions of ‘date’, ‘--rfc-2822’ and ‘--rfc-822’ are aliases for
‘--rfc-email’.
‘--rfc-3339=TIMESPEC’
Display the date using a format specified by Internet RFC 3339
(https://tools.ietf.org/search/rfc3339). This is like
‘--iso-8601’, except that a space rather than a ‘T’ separates dates
from times. This format is always suitable as input for the
‘--date’ (‘-d’) and ‘--file’ (‘-f’) options, regardless of the
current locale.
The argument TIMESPEC specifies how much of the time to include.
It can be one of the following:
‘date’
Print just the full-date, e.g., ‘2005-09-14’. This is
equivalent to the format ‘%Y-%m-%d’.
‘seconds’
Print the full-date and full-time separated by a space, e.g.,
‘2005-09-14 00:56:06+05:30’. The output ends with a numeric
time-offset; here the ‘+05:30’ means that local time is five
hours and thirty minutes east of UTC. This is equivalent to
the format ‘%Y-%m-%d %H:%M:%S%:z’.
‘ns’
Like ‘seconds’, but also print nanoseconds, e.g., ‘2005-09-14
00:56:06.998458565+05:30’. This is equivalent to the format
‘%Y-%m-%d %H:%M:%S.%N%:z’.
‘-s DATESTR’
‘--set=DATESTR’
Set the date and time to DATESTR. See ‘-d’ above. See also ⇒
Setting the time.
‘-u’
‘--utc’
‘--universal’
Use Universal Time by operating as if the ‘TZ’ environment variable
were set to the string ‘UTC0’. UTC stands for Coordinated
Universal Time, established in 1960. Universal Time is often
called “Greenwich Mean Time” (GMT) for historical reasons.
Typically, systems ignore leap seconds and thus implement an
approximation to UTC rather than true UTC.
Info Catalog
coreutils: Setting the time
coreutils: date invocation
coreutils: Examples of date